From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757698Ab1KPCNd (ORCPT ); Tue, 15 Nov 2011 21:13:33 -0500 Received: from out01.mta.xmission.com ([166.70.13.231]:42334 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753800Ab1KPCNc (ORCPT ); Tue, 15 Nov 2011 21:13:32 -0500 From: ebiederm@xmission.com (Eric W. Biederman) To: Greg KH Cc: Markus Trippelsdorf , linux-kernel@vger.kernel.org References: <20111113192417.GA1659@x4.trippels.de> <20111116003949.GA15882@suse.de> Date: Tue, 15 Nov 2011 18:14:34 -0800 In-Reply-To: <20111116003949.GA15882@suse.de> (Greg KH's message of "Tue, 15 Nov 2011 16:39:49 -0800") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-XM-SPF: eid=;;;mid=;;;hst=in01.mta.xmission.com;;;ip=98.207.153.68;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1/U0dqGC9h726Z67HXDKpDIo5gWF2zwzSc= X-SA-Exim-Connect-IP: 98.207.153.68 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Report: * 1.5 TR_Symld_Words too many words that have symbols inside * 0.0 T_TM2_M_HEADER_IN_MSG BODY: T_TM2_M_HEADER_IN_MSG * -3.0 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa01 1397; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_XMDrugObfuBody_14 obfuscated drug references * 0.0 T_TooManySym_01 4+ unique symbols in subject * 0.4 UNTRUSTED_Relay Comes from a non-trusted relay X-Spam-DCC: XMission; sa01 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ;Greg KH X-Spam-Relay-Country: ** Subject: Re: WARNING: at fs/sysfs/sysfs.h:195 (during boot) X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Fri, 06 Aug 2010 16:31:04 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Greg KH writes: > On Sun, Nov 13, 2011 at 08:24:17PM +0100, Markus Trippelsdorf wrote: >> I'm seeing this for the fist time: >> >> ... >> XFS (sda): Mounting Filesystem >> XFS (sda): Ending clean mount >> ATL1E 0000:02:00.0: irq 40 for MSI/MSI-X >> ATL1E 0000:02:00.0: eth0: NIC Link is Up <100 Mbps Full Duplex> >> ATL1E 0000:02:00.0: eth0: NIC Link is Up <100 Mbps Full Duplex> >> udevd[888]: starting version 171 >> ------------[ cut here ]------------ >> WARNING: at fs/sysfs/sysfs.h:195 sysfs_get_inode+0x136/0x140() >> Hardware name: System Product Name >> Pid: 945, comm: udevadm Not tainted 3.2.0-rc1-00252-g8f042aa #49 >> Call Trace: >> [] warn_slowpath_common+0x75/0xb0 >> [] warn_slowpath_null+0x15/0x20 >> [] sysfs_get_inode+0x136/0x140 >> [] sysfs_lookup+0x6f/0x110 >> [] d_alloc_and_lookup+0x39/0x80 >> [] do_lookup+0x283/0x390 >> [] path_lookupat+0x114/0x6d0 >> [] ? getname_flags+0x36/0x230 >> [] do_path_lookup+0x2b/0x70 >> [] user_path_at_empty+0x58/0xb0 >> [] ? sysfs_put_link+0x1c/0x20 >> [] ? generic_readlink+0x84/0xa0 >> [] user_path_at+0xc/0x10 >> [] vfs_fstatat+0x30/0x70 >> [] ? mntput_no_expire+0x2b/0xe0 >> [] vfs_stat+0x16/0x20 >> [] sys_newstat+0x15/0x30 >> [] ? sys_readlinkat+0x7e/0xb0 >> [] system_call_fastpath+0x16/0x1b >> ---[ end trace 2226f614d7765573 ]--- >> Adding 2097148k swap on /var/tmp/swap/swapfile. Priority:-1 extents:2 across:2634672k >> >> fs/sysfs/sysfs.h:195: >> WARN_ON(!atomic_read(&sd->s_count)); > > Odd, is it reproducable? > > Eric, any ideas? So this indicates we found a sysfs_dirent in a directory with a reference count of 0. If this isn't caused by a bitflip. My guess would be something off in the new sysfs directory handling. Off the top of my head I don't know how the new sysfs directory handling could have caused this. But I expect it would take a fair amount of directory modification to cause this. Everything is serialized under the sysfs_mutex so it should be really hard to trigger race conditions. I am scratching my head. Eric